class_docstr: Base class for all other trainer classes.
  
  :param boolean show_training_progress: Show progress indicators for the
         trainer. The environment variable ``CHATTERBOT_SHOW_TRAINING_PROGRESS``
         can also be set to control this. ``show_training_progress`` will override
         the environment variable if it is set.
docstr: This method must be overridden by a child class.
docstr_tok: ["This","method","must","be","overridden","by","a","child","class","."]
code: def train(self, *args, **kwargs):
      """
      This method must be overridden by a child class.
      """
      raise self.TrainerInitializationException()
  
imports: import os
  import sys
  import csv
  import time
  from dateutil import parser
  from chatterbot.conversation import Statement
  from chatterbot.tagging import PosLemmaTagger
  from chatterbot import utils
label_desc: Use image node_id 3 for calling the Trainer obj's underlying member method code with example usage: obj.train() without return types